ML17193B297

Forwards Revised Tech Spec Table 3.6.1,removing Snubbers 18, 19 & 20 from HPCI Sys Piping,In Support of 810401 OL Amend Application.Max Piping Stress Is Above Allowable Limit W/Snubbers Present

ML17193B297
Person / Time
Site:	Dresden
Issue date:	04/03/1981
From:	Janecek R COMMONWEALTH EDISON CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
Shared Package
ML17193B298	List: ML17193B297 ML19343D118
References
NUDOCS 8104090484
Download: ML17193B297 (2)

Text

Commonwealt9dison One First Nationr;il Plaza, Chicago, Illinois Address Reply to: Post Office Box 767 Chicago, Illinois 60690 April 3, 1981 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

Dresden Station Unit 3 Proposed Amendment to Appendix A, Technical Specifications, to Facility Operating License DPR-25

'NRC-Docket-No~*50~249- * - - * - *

• Reference (a): R. F. Janecek letter to H. R. Denton dated April l, 1981.

Dear Mr. Denton:

Reference (a) transmitted a request for amendment to the Technical Specifications for Dresden Unit 3 to remove as many as three safety-related s~ubbers from the HPCI system piping. As committed to in Reference (a), the following additional information provides further definition and support for _the requested amendment.

Our detailed system stress analysis has indicated that all three (3) snubbers, numbers 18, 19 and 20 in.Technical Specification Table 3.6.l, need to be Yemoved. Attached is a revised page 9le wh i c h i nc l ud e s t h,e >S n u bb e r r em o v a l s

• The three snubbers are attac~ed to the *piping at the same location. Stress analysis of the existing system indicated that with the snubbers present, the local stress at the snubber-to-pipe attachment was greater than the material ultimate' stress of 60,000 psi. Following removal of the snubbers, the maximum piping stress due to seismic loads is reduced to below the IE Bulletin 79-14 operability limit.

Please address any additional questions concerning this matter to this office.

~ery truly yours,

~~---'c..-~~~~~~~~~~- ~'-**JUA//~=--::::::~~~~~~~

Robert F. Janecek

.Nuclear Licensing Administrator Boiling Water Reactors cc: Rill Inspector - Dresden {

l996B 810409013'1

. -.. :..: . ..i~~:~.L-l:'___: .. *,t . . . i"  ;* . : *.* . : :i;.' *.. *:?:.-

• • • -*--**--****--'...*---------***-*-**- ... -* .. --~....:.:: .

• ~,-

Table 3.6.1 (Continued) SAFETY RELATED SHOCK ......... t'PRESSORS (SNUBBERS) ~

~-~

.. i

~ *Snubbers Snubbera ..

• i Snubber in High_* Inacces~lhlo Accessible Radiation Area Diid113 llor.rr,al During Nonr,al Snubber No. Location ' Elevation Azimuth During .. Shutdown_ Operations Opor::itic'f'\S 13

• 0:-ywell Recirc. ~1ne 201::3-28" 507' 305° x 14 15 Dr;r.1ell Recirc. Lino *2c1A-28 11 LPCI Line 1506-16 11 -

507' 105° ...,.

.\..

x 16 DrY1.1dl 513' -2~6° I. x*

Drywcll LPCI Line 1519-16" 513* 95° x x -'I 17 .

Dr\'~1e 11 :te ci re

• Header ?.01B-22"

\ 533 1 6 11 195° I. x I

i 18 Rerroved

! 19 Removed 20 Rerroved

• 1 i 21 Di*yWcll ReciI-c. Header ?OlA-22 11 22° 533 1 6 11  :{ 1.

i 22 Dr:i-wcll HPCI Line 2 J05-J 0 11 550' 121°  ;( x i 23 Drywell Cle:inup Line 1201-8 11 537 1 6 11 ".

i 24 llrywcll Feed:-1a ter Line )20!'1)-12 11 e4°  ;{ x ..

• ' 5J8' 106° l. x ....

25 Dr.)-...itill Cleanup Line 1201-8" 537 6 1 11 78° x

.t.

26 Orywcll Feed.,.ater Line 3::?0!µ\-18" 537 1 6 11 66° x

j 27 Dc~....:ell Cleanup Line 120l-8i1 53[}16 11 60°  :<  :;c  ! *.

28 Drywell Feed~nter Line )204C-12 11 540 1 73° '/. x

'l ..

I 29 DryH:!ll Core Spray Line lll04-10 11 573' 231° x x ....

30 Dr;,*well Core Spt*ay Line 140)-10" 563' JJ6° *x x 31 o-*

ur;r*;ell HPCI Line 2305-10" 56)' 140° x x (>O

~

.32 33 Drywcll Target Rock Valve 203-JA 542 16 11 14° "( x Q 34 Drywell Tnrcet Rock Valve 203-)A 542 1 2 11 31° x x ' ~

35 Dry:1cll Target Rock Valve 203-JA 540' 19° x x* 0 Dryucll TarGet Rock Valve 203-JA 540 16 11 34° x x ~

Isolation Condenser Pipew3y*nooms Iso. Cond. Line 1303-12 11 x 0

1 Is6. Cond. Line 1303-12 11 558* 180° x GO 2 568' x

~

180° 1 3 Iso~ Cond. Line 1302-141 580 1 -195° *:c x j

j

• Modifications to this table due to changes in high radiation should be ..

submitted to.the NRC as part of the next license amendment request. 9le I ~